Ring Nebula

Ring Nebula
Emission nebula
Planetary nebula
	The Ring Nebula as seen in infrared and visible light by a multiple exposure of images from the James Webb Space Telescope's NIRCam, showing an outer layer of hydrogen that is very faint in visible light
Observation data: J2000 epoch
Right ascension	18h 53m 35.079s
Declination	+33° 01′ 45.03″
Distance	2567±115 ly (787±35 pc)
Apparent magnitude (V)	8.8
Apparent dimensions (V)	230″ × 230″
Constellation	Lyra
Physical characteristics
Radius	1.3+0.8; −0.4[a] ly
Absolute magnitude (V)	−0.2+0.7; −1.8[b]
Designations	M 57, NGC 6720, GC 4447.
	See also: Lists of nebulae

The Ring Nebula (also catalogued as Messier 57, M57 and NGC 6720) is a planetary nebula in the northern constellation of Lyra.^[4]^[C] Such a nebula is formed when a star, during the last stages of its evolution before becoming a white dwarf, expels a vast luminous envelope of ionized gas into the surrounding interstellar space.

^ ^a ^b ^c ^d ^e ^f "M 57". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2006-12-19.
^ Murdin, P. (2000). "Ring Nebula (M57, NGC 6720)". In Paul Murdin (ed.). Encyclopedia of Astronomy and Astrophysics. Institute of Physics Publishing. Bibcode:2000eaa..bookE5323.. doi:10.1888/0333750888/5323. ISBN 978-0-333-75088-9. Article ID #5323.
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